


Black Moon Fang

by LourdesDeath



Series: What is the difference between a king and his horse? [1]
Category: Supernatural
Genre: Gen, deanmon
Language: English
Status: Completed
Published: 2014-10-28
Updated: 2014-10-28
Packaged: 2018-02-23 01:09:08
Rating: Teen And Up Audiences
Warnings: Graphic Depictions Of Violence
Chapters: 1
Words: 3,960
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/2528423
Author URL: https://archiveofourown.org/users/LourdesDeath/pseuds/LourdesDeath
Summary: <blockquote class="userstuff">
              <p>The Demon Cure was less effective than everyone believed. (Post-ep to 10.03 'Soul Survivor'.)</p>
            </blockquote>





	Black Moon Fang

**Author's Note:**

> Special thanks to [ Johnlock-Deductress](http://archiveofourown.org/users/KeitanKetsueki/pseuds/Johnlock-Deductress) for beta reading and fixing my story (and my notes). Also to Kubo Tite, for the inspiration.

_Dean._

There was no light, but it wasn’t dark, either. He was surrounded by…nothingness… How long had he been here? Hours? Years?

He couldn’t feel anything, as if he was in a pool of water that had absorbed him, and his skin wasn’t where he ended anymore. Occasionally, he’d feel distant sensations—something in his hand, a ghost of a caress—but they came and went before he could begin to comprehend what they meant.

_Dean._

Far above him, a pinprick of light appeared. It flickered, a single star in the midnight black sky, and started to grow. For a moment, it was big enough for him to see colors dancing inside the light. There was a voice, too. Familiar… so familiar.

_Dean._

A sudden cacophony of noise barraged his eardrums—screams, sirens, slamming doors. And there was pain—so much pain—radiating from his arms and neck. His blood boiled, his skin felt like it was being burnt off.

The light vanished, a candle snuffed out. The voice was gone. Peace had returned. No light, no pain, no sound. Just floating.

_Dean._

Then, the light returned, larger and brighter than before. The colors and the sounds were back. It was so bright that his eyelids were no protection from it. Screaming. A monster roaring. Was it coming for him?

The light faded. Two people were speaking. They sounded nearby.

He opened his eyes again. Sammy and Cas were there, staring at him. His arms were bound to a chair. There were no colors, then, in a flash of light, everything became almost painfully saturated. A loud ringing pierced his eardrums and he shook his head in a vain attempt to relieve himself of the noise.

When he looked back up, Sam and Cas shifted, like they expected him to try to attack them.

 “You look worried, fellas,” he said, trying to calm them down.

Sam splashed holy water on him, and he flinched. The water dripped down his face.

“Welcome back, Dean,” Sam said, grinning.

‘Back’? He looked to Cas for an explanation, and was shocked to see the angel wearing a smile of his own.

_Dean._

For a second, he felt angry; a part of him wanted to kill them. Dean’s mind treated him to the image of Cas kneeling over Sam’s broken and lifeless body as blood poured down his back, an angel blade being thrust into his throat, the light from his eyes and mouth almost blindingly bright.

\--

“I’m sorry, Sam.”

Sam stopped on his way out the door. He’d hardly looked Dean in the eye while explaining everything that had happened. Dean couldn’t figure out why—after all, Sam wasn’t the one who should be feeling guilty—but he turned around and finally _looked_ at Dean. “You don’t have to be sorry, Dean. It…” He looked away, like he thought the room could help him find the right words. Dean realized Sam’s eyes had paused on the stack of pictures on his nightstand. “It wasn’t your fault, Dean. That wasn’t _you_.”

How could Dean believe that?

“I’m gonna get you some food, okay?”

Dean nodded, but he didn’t trust his voice to work.

And then Sam was gone. Dean leaned back against his headboard and closed his eyes, trying to clear his head.

_Dean._

\--

“I don’t know, Dean.”

“C’mon, Sammy. I’ve been resting for over a week. I’m _fine_.”

Sam got that worried look of his where he pressed his lips together and wrinkled his forehead.

“Look, man, I’m not asking to go out and kill every demon in America, I just want to go out and do a simple little job,” if it sounded like Dean was whining, he ignored it. “Ghosts are hardly even worth the gas it takes to find them. Hell, I could deal with a ghost with an arm tied behind my back.” Sam was unconvinced. “It’s in Colorado, so it’s not even that far.”

Rereading the printouts Dean had given him, Sam frowned. “It _does_ look like a normal haunting.” He rubbed his forehead and sighed. “Okay, but I’m coming with you.”

“I wouldn’t have it any other way.”

\--

Sam mentioned that Dean had been neglecting Baby while he was…incapacitated, and had been kind enough to clean the interior before letting Dean see her, but even without any visible evidence of negligence, Dean could swear the upholstery still smelled like greasy food.

In spite of that, he gave the steering wheel an appreciative stroke after he started the engine.

“I’m sorry, Baby,” he whispered as Sam struggled his way into the passenger seat. “I’ll never mistreat you again.”

Smiling, Sam glanced at him. “You two need a moment?”

The comment was clearly in good fun, so Dean responded by aiming a pout at his brother. “Sam could never understand our love, could he, Baby?”

That got a chuckle out of Sam, which was certainly an improvement on the concerned expressions that had plagued his features since Dean was healed.

Popping Black Sabbath into the tape player, Dean revved the engine and pulled out of the garage.

They didn’t speak much as they drove. Dean couldn’t bring himself to sing to any of his favorite songs, and Sam kept falling asleep.

_Dean._

He’d heard that voice in the bunker and had passed it off as nothing, but he turned off his music to listen. The voice didn’t come back.

After a while, they stopped at a gas station. Sam took over filling the tank while Dean answered the call of nature. The bathroom was a single person affair, which was a blessing and a curse. On the one hand, he wouldn’t catch any truckers bumping uglies, but small gas stations meant small staffs, and small staffs meant they didn’t clean the bathrooms often enough.

Avoiding contact with any surfaces, Dean washed his hands and checked his hair in the (graffiti-covered, mystery substance-crusted) mirror.

Was he seeing things or was his reflection _smiling_ at him?

He reached up to the mirror, his reflection did _not._

 _“Hey, Dean,”_ his reflection said. “ _I thought it was about time we had a little chat, and since you keep ignoring me, I had to come to you.”_

“Who are you?”

 _“Who am I?”_ his reflection scoffed and Dean felt sick when he saw his reflection’s eyes become black.  “ _I’m_ you. _I’m the one who was in charge while you were out of commission.”_

“You’re supposed to be gone. Sam healed me.”

 _“Yeah, he did, but the demon blood’s only part of your problem.”_ He turned his arm and Dean’s own arm followed it. The Mark of Cain glowed on his skin. _“Cain warned you that the Mark would be a burden; you chose not to listen,”_ his doppelgänger smirked. _“It’s only a matter of time before you lose control again, and this time, the cure won’t work. We’re both human, I’ve just got a few extras.”_

“I’ll kill you.”

_“You’ll have to kill yourself first. And when we go to Hell—and we will—I’ll be the one in charge.”_

“I won’t let that happen.”

_“There’s no other choice. You’ll lose to me, then I’ll make you watch while I gut your precious little brother and rip the wings off that angel.”_

\--

Dean regretted punching the mirror, but, like he—no, _the demon_ —had predicted, he’d lost control.

Luckily, Sam had already used the bathroom, so there were no uncomfortable questions about what had happened. He’d tell Sam eventually, but if there was any chance of him dealing with this on his own, he’d do it. Sam had already dealt with so much crap because of the demon, and he wanted to give the poor kid a rest.

But he couldn’t help flinching when he saw his own reflection in the rear-view mirror and noticed the black that was bleeding into his right eye.

\--

By the time they realized two ghouls were working with the ghost, it was too late to call for help from any nearby hunters. Dean had tried praying to Cas, but there was no answer. No fluttering of wings accompanied by that ridiculous trench coat.

They had found the remains of the ghost on a watch under a loose floorboard in the abandoned house and managed to burn them just as the ghouls caught them.

Sam was unconscious: the larger of the ghouls had slammed his head into a wall.

All of the weapons were on the other side of the room: the salt, the guns, the knives—hell, even his lighter. The other ghoul was on top of him, hands in a vice grip around his throat.

The edges of Dean’s vision started to go dark; he knew he wasn’t going to make it. He and Sam were going to die like a pair of newbies on their first hunt.

Opening its maw, the ghoul leaned in. It was going to start eating him before he was even dead. Or maybe he’d suffocate before it even had a chance to start. At least that way he could die in one piece.

Everything went black.

_Dean._

He could barely see through the darkness, but Dean could feel his arms reaching up to the ghoul and his fingers curling around its neck.

The ghoul was pulled down until it was almost laying on Dean, then he threw it across the room. The other ghoul slammed into him as he stood up, but Dean’s only response was to rock on his feet. With his left hand, he grabbed the ghoul’s left shoulder and, crossing right arm over his left, he grabbed the ghoul’s face and ripped its head off.

 _“I told you, Dean,”_ his body said, _“If you die, I’m in control. Of course, I want my body as close to mint condition as possible when I get ahold of it, so don’t worry about being eaten by some abomination like these sons of bitches.”_

Blood dripped from his face and hands as he walked to the remaining ghoul. It was clearly trying to find an escape route, but Dean’s body had cornered it.

Slowly—almost casually—Dean’s body reached down and picked up one of the knives that littered the floor. His lips curled into a grin as he flipped it in the air and caught it by the handle.

In a last-ditch effort for survival, the ghoul attacked him, leaping up and trying to grab the knife. Dean’s body dodged and thrust out his leg, tripping the ghoul. It fell to the ground and Dean’s body plunged the knife into its neck, feeling the resistance of its spinal cord as he tore through flesh, blood spraying him.

Dean’s body got to its feet and wiped the blood off his mouth with the back of his hand.

“Dean…?”

He turned.

Sam was awake. That kid had always had perfect timing. He was still on the ground, but he’d pushed himself up with his one good arm. “Dean, what are you…” He looked up into his brother’s eyes and realized their color. “Dean?” he whispered.

 _“Hey, Sammy,”_ the demon said. _“Miss me?”_

“You—”

Anything Sam wanted to say was cut off by Dean’s boot pressing against his trachea. Dean was reminded of a different time: a man in white, the thundering of automatic gunfire, and a life—a world—ended with the sound of snapping bone.

_“Let’s not spoil this moment with words, Sammy.”_

Dean could see Sam’s jaw working as he tried to breathe, but he didn’t have enough leverage to break free.

Twirling the knife between his fingers, the demon chuckled to himself. _“You know, Sam, I gotta thank you. At first, I thought we could just go our separate ways, but you turning me human…”_ he put so much weight on Sam’s neck that Dean—the _real_ Dean—feared for Sam’s life. _“Well, that just showed me how much I really want to kill you.”_

There was a fluttering of wing behind him and, for a moment, Dean had a glimmer of hope. Cas was strong enough to stop the demon.

Unfortunately, the demon also heard the angel’s entrance. He released Sam and lunged at Cas, an inhuman roar tearing through his throat.

Dean’s fingers curled around one of Cas’s lapels, the other swung for his jaw.

Cas grabbed the fist and lifted a snarling and clawing Dean off the ground by his neck. “You have to fight it, Dean. You need to stop it.”

Dean gaped at him from his dark prison. Fight it? He couldn’t even control his own body—let alone fight.

The demon wrapped Dean’s fingers around Cas’s arm and the angel’s borrowed features twisted in pain as smoky black marks crawled up from under his collar.

“No!” Dean shouted, and he used every ounce of his willpower to pull his hand away from Cas.

His arm froze, then dropped to his side.

Dean looked down into the midnight world and saw one arm. The rest of his body, if it was there at all, was still trapped in the darkness.

Maybe he _could_ fight the demon.

Dean shifted his gaze from the light to the eternal darkness imprisoning him. With his surroundings dark, he could only distantly feel what his body was doing.

His legs were kicking against Cas’s; Dean focused on his left leg first. He could see his bones, bound in muscle and wrapped in skin. Black smoke swirled around the image of his limb in his mind, a visual representation of the demon’s control. He imagined light shining through the darkness, the kind of light he’d seen coming from Cas whenever he smote a demon.

The smoke shied away from the light, leaving the leg inch by inch.

Dean tensed his leg and felt it obey him.

Okay, that wasn’t too hard.

Repeating the process with his right leg, Dean felt almost no resistance from the black smoke. The moment he turned the light on, it vanished.

It was starting to feel too easy. Why would the demon just give up like that? He wanted control as much as—if not more than—Dean.

Just as he decided to concentrate on his right arm, he heard Sam call out, “Fight it, Dean! You can do this!”

His focus shattered and Dean felt his right leg start kicking again, while the other twitched against his will.

Great. Sam’s perfect timing had struck again.

Dean glared behind him at the pool of light that showed him the outside world. Sam was probably still behind him—all he could see was Cas, who had continued to hold him up off the floor. His face was neutral now, but the black marks had returned. His eyes glowed blue.

Cas was using mojo that he didn’t have to spare.

He needed to work quickly.

Dean returned to that inner place where he could see his body and the smoke that surrounded it. His left leg was easy to retake, and the smoke had gone before he even looked at his right leg.

He realized why his legs were so easy to claim when he finally focused on his right arm. It was obscured in so much smoke that it was nearly indiscernible from the darkness surrounding Dean. The smoke seemed to be coming from the Mark of Cain, which was glowing an angry red and was luminous, even behind all that smoke.

Clearly the demon _hadn’t_ given up.

Dean got to work, creating that light he’d used before. This smoke was far less susceptible to its rays. Even when his light shone brighter than it had been for any of his other limbs, the smoke hardly reacted, but Dean persevered. There was no way he would put Sam and Cas through the pain of killing him, just because he had given up.

It took what felt like hours, but eventually Dean had rid the arm of smoke. He flexed his fingers, pleased with his regained control.

Then, Dean realized that he still had a problem: even if he’d gotten his limbs back, he was still in the weird limbo world where he’d been all along. He’d stopped trying to kill Cas, but he wasn’t about to spend the rest of his life in whatever this place was.

As if his thoughts were some sort of mental Portkey, Dean found himself transported to the shores of a lake surrounded by trees. A fishing rod was set up in front of him.

Laughter distracted him away from the lake, and Dean looked over to see Sam—as he was when he was in his early teens—a few hundred feet away. He almost thought he had somehow been sent to heaven again, but the presence of Cas (who was commenting on a few plants Sam was showing him) made him believe otherwise.

 _“Hey, Your Highness,”_ someone said behind him.

Spinning to face this person (who he instinctively knew did _not_ belong here), Dean was struck by the intruder’s face.

Dean was no stranger to having conversations with himself—meeting yourself in the future isn’t something you forget easily—but while that Dean had just looked like an older, broken down version of himself, _this_ Dean was all wrong. His hair was unlike any style Dean had ever worn, his eyes were pitch black, and his mouth was wide enough to make his smirk look inhuman. He stood just beyond the tree line, shadows playing across his body.

“Who are you?”

The Joker wannabe’s smile grew even wider. _“I’m_ you _, Your Highness. The_ real _you, not troubled by all the issues that cloud that mind of yours.”_

“You’re the demon?”

 _“Nothing gets past you, does it, Your Highness?”_ The shadows surrounding the demon moved against the shadows falling from the trees, sometimes becoming so thick Dean could hardly see him.

“Why are you calling me that?”

Leaving the protection of the trees, the demon answered. _“You’re the king of this world—at the moment.”_

Dean moved so the demon would have to get through him if he wanted to attack Sam or Cas.

 _“Don’t be an idiot,”_ the demon said, clearly understanding Dean’s stance. _“Why would I attack them? They’re not real.”_ He stopped several feet away. _“If I’m going to attack someone, I’m going to attack_ you _.”_

“Go ahead and try.”

_“Sorry, your Highness. Unlike you, I’m content with waiting. I know I’ll win in the end, so I have nothing to worry about.”_

“Is that why you let me take back control of everything?”

 _“Close, but no cigar,”_ the demon replied, looking out onto the lake. _“That was just the easiest way to get you here.”_

Dean followed his gaze and saw a tiny whirlpool at the center of the lake, like someone had pulled the plug out of an old-timey bathtub.

“What is that?”

 _“Me.”_ The demon looked back at him, and Dean watched its shadow flicker. _“Eventually, all of this will be eaten up by me, and you won’t be able to fight anymore. I gave up a few limbs so we could have a little chat.”_

“Trying to tell me resistance is futile?”

 _“Even you’re smart enough to figure_ that _out on your own.”_

“Then what do you want from me?”

The shadow at the demon’s feet shifted between shapes, sometimes becoming that of a monolith, other times looking like a child’s shadow. _“Everything you have, so basically nothing.”_

“So, that’s why you took over?”

_“Like I said, I just wanted to have a chat. We’ve been together a long time and we’ve never talked before.”_

“A few months isn’t a long time.”

_“’A few months’? I’ve had my claws in you a lot longer than that, your Highness.”_

“What?”

_“I’ve been here since the day you went to hell. I just didn’t really feel like playing with Alastair or the Archangels. So, I waited.”_

“Until I got the Mark.”

_“I had a feeling you’d get it eventually. You’re descended from him, and you and Sammy are cut from the same cloth as Cain and Abel.”_

Dean worked his jaw. The demon was provoking him, and responding would only prove him right.

_“I can’t wait to destroy this little world of yours. It’s gonna feel so good to tear your mind apart piece by piece.”_

“I won’t let you.”

 _“The time for threats has passed, Your Highness,”_ the Joker-smile returned. _“I’ll let go of your body for now, but don’t worry. I’ll be back soon.”_

With that, the bottom dropped out of Dean’s world. As he started to fall, Dean kept watch on the demon, who smirked nastily. The dark forest around him morphed into nothingness under a cloudy, moonlit sky. The clouds wreathed the moon so that it took the appearance of a fang.

Turning away, the last thing Dean saw was Sam and Cas, oblivious to his or the demon’s presence, still at the edge of the lake. The demon’s world of nothingness was coming for them, too.

Darkness surrounded him once again.

\--

“Dean! Dean!” Sam was shaking him. “Wake up!”

Groaning, Dean opened his eyes and flinched when water was splashed on his face. If this was going to be a common occurrence, he was going to have to start carrying around a towel or something to keep dry.

“Dude, it’s me,” he mumbled, wiping his face on the back of his sleeve.

Neither Sam nor Cas looked convinced. Cas was even doing that squinty thing with his eyes. None of them moved.

“What?” Dean said. Did they think he was the demon, or something?

“Your eye is…” Sam didn’t finish the statement.

“ _What?_ ”

Sam handed him the flask of holy water, and Dean looked at his reflection on the back. His left eye was normal, but his right eye had black bleeding into it, like he’d seen during the drive to Colorado.

“It would seem the demon still has a hold on your mind. How did you fight it off?” Cas asked, still staring at Dean.

“He kinda let me.”

Cas frowned. “Why?”

Sighing, Dean stood up. He couldn’t take much more hovering. “He said he’d get control in the end, so there was no point fighting me now.”

“We need to remove the Mark of Cain, it’s our only chance of stopping the demon.”

“He said he wasn’t caused by the Mark, that he’d been… a part of me since I was in Hell.”

“That isn’t possible. I removed you from Hell myself, I would’ve known if there was a demonic entity attached to your soul.”

“Look, man, I’m just saying what he told me.” Dean could see guilt written all over Cas’s face. “I’m not blaming you, Cas.”

Dean was going to punch something if the two of them kept on with those concerned glances at his eyes.

“I’m fine. We’ll get through this like we’ve gotten through everything else.”

“But if—” Sam started, but Dean cut him off.

“If it makes you feel better, I won’t go on major hunts. I’ll even try to avoid demons.”

“That would probably be for the best,” Cas replied.

They both relaxed a little, which calmed Dean’s nerves.

“Let’s get the hell out of here. I’m freaking starving.”

“Dude, is there anything that can kill your appetite?” Sam asked, a tentative smile gracing his lips.

Dean beamed back at him. “Probably not.”

“I can think of quite a few things that are likely to—”

“It was a joke, Cas.”

It was just like old times, a big, scary monster threatening everything Dean loved, but him having faith in them being able to beat the odds if they stuck together.

As they left the run-down house, Dean felt a presence like a snake gliding through the back of his mind.

_Dean._

**Author's Note:**

> Yes, this was inspired by the whole Hichigo thing in BLEACH. If you think about it, there are a shocking number of parallels.


End file.
